Concrete wall form tie rod assembly with twist-off spacer members

ABSTRACT

A concrete wall form tie rod assembly in which the tie rod has (a) looped ends for connection to opposed and spaced apart wall form panels, (b) breakbacks by means of which the rod may be fractured in order to permit removal of the looped ends of the tie rod from the hardened concrete wall, and (c) molded torque receiving plastic spacer members which are of special construction and make such interlocking engagement with the looped ends of the tie rod that, when said looped ends are twisted, the spacer members are wrested from the hardened concrete wall along with the looped ends of the tie rod.

United States Patent [191 Jan. 115, 1974 Dagiell [75] Inventor: RichardT. Dagiel, Elk Grove Village, 111.

[73] Assignee: Symons Corporation, Des Plaines,

22 Filed: Mar. 6, 1972 211 Appl.No.:232,072

3,653,628 4/1972 Shoemaker 249/43 3,490,730 1/1970 Gates 249/43 4/1969Gates 249/43 Primary Examiner-Robert D. Baldwin Assistant ExaminerJohnMcQuade Att0rneyNorman H. Gerlach [57] ABSTRACT A concrete wall form tierod assembly in which the tie rod has (a) looped ends for connection toopposed and spaced apart wall form panels, (b) breakbacks by means ofwhich the rod may be fractured in order to permit removal of the loopedends of the tie rod from the hardened concrete wall, and (c) moldedtorque receiving plastic spacer members which are of specialconstruction and make such interlocking engagement with the looped endsof the tie rod that, when said looped ends are twisted, the spacermembers are wrested from the hardened concrete wall along with thelooped ends of the tie rod.

4 Claims, 5 Drawing Figures CONCRETE WALL FORM TIE ROD ASSEMBLY WITHTWIST-OFF SPACER MEMBERS The present invention relates generally to aconcrete wall form tie rod assembly and has particular reference to anovel spacer member which is installed upon the tie rod of the assemblyand functions in the manner of a conventional spacer cone to assimilateany inward thrust that may be exerted thereon by the adjacent wall formpanel and also to exclude the flow of wet concrete into the hole oropening where the tie rod passes into the confines of the adjacentpanel-formed side of the associated concrete wall form, but which ismore easily extracted from its position of embedment in the surfaceregion of the hardened concrete wall after the various wall form panelsconstituting the two opposed and spaced apart sides of the form havebeen stripped from the finished or completed wall. The invention isspecifically concerned with a tie rod assembly of the type in which thetie rod proper is formed from cylindrical wire or rod stock and hasreentrant looped ends which constitute fastening means for tie rodanchoring purposes so that the tie rod may be connected at its ends tothe opposed and spaced apart sides of the associated concrete wall form,the assembly including on the tie rod rigid spacer members which are offrusto-conical design and are telescopically received over the tie rodin the vicinity of the latters looped ends. In the erected concrete wallform, these frusto-conical spacer members assume positions close to orin contact with the inner concrete-receiving faces of the opposed andspaced apart sides of the associated concrete wall form so that, afterthe concrete is poured into the space between the sides of the form andhas become hardened, they remain embedded in the resultant side surfacesof the wall while the looped ends of the tie rod project forwardly ofthe spacer members through the adjacent form sides and are thus exposedfor twist-off purposes. The tie rod is usually weakened near the innerends or small bases of the two frusto-conical spacer members in order toenable the projecting looped ends of the tie rod to be twisted and thussevered from the concreteembedded media] or intermediate region of thetie rod, thus leaving the spacer members countersunk withincomparatively deep sockets in the side surfaces of the finished orcompleted concrete wall. In order to facilitate extraction of thesespacer members from the sockets in which they are embedded, the membersusually are of frusto-conical configuration as previously pointed out,thus giving rise to the name spacer cone or spreader cone which has longbeen applied to such spacer members regardless of whether they are trulyfrusto-conical, cylindrical, or some other configuration. Such rigidspacer members or cones are frequently extremely difficult to extractafter use and, if the application of twisting force to them is notsufficient to dislodge them from their bonded relationship within theirrespective sockets in the side surfaces of the hardened and finishedconcrete wall, they must be intentionally fractured and then removedfrom the sockets in piecemeal fashion.

The tie rod assembly of the present invention is designed to overcomethe above-noted difficulty which is encountered in the extraction ofconventional spacer members or cones from their positions of embedmentin the side surfaces of a concrete wall and, toward this end, theinvention contemplates the provision of a tie rod assembly in which thespacer members that are associated therewith are formed of a relativelyhard, rigid plastic material, present smooth outer surfaces forinhibiting binding of the members to the hardened concrete, and areinterlocked with the looped ends of the tie rod so that, after thepanels of the concrete wall fomi have been stripped from the completedhardened concrete wall, the usual rotational twisting of the looped endswill apply torque to the spacer members, first, to break the bondbetween the outer surfaces of the members and the concrete and,secondly, to pull the spacer members from their respective sockets inthe side surfaces of the completed concrete wall.

Apart from the application of rotational torque to the frusto-conicalspacer members for ease of removal of the spacer members, an additionaladvantage of the invention resides in the fact that the plastic spacermembers are reuseable since they are not damaged, deformed, or destroyedin the process of extracting them from their respective sockets in theside surfaces of the finished concrete wall.

The provision of a tie rod assembly embodying plastic frusto-conicalspacer members such as have briefly been outlined above constitutes theprincipal object of the present invention. Other objects and advantagesof the invention, not at this time enumerated, will become readilyapparent as the nature of the invention is better understood from aconsideration of the following detailed description.

The invention consists in the several novel features which arehereinafter set forth and are more particularly defined by the claims atthe conclusion hereof.

In the accompanying single sheet of drawings forming a part of thisspecification, one illustrative embodiment of the invention is shown.

In these drawings:

FIG. 1 is a fragmentary top perspective view of a concrete wall formemploying a plurality of tie rod assemblies embodying the principles ofthe present invention;

FIG. 2 is a fragmentary top perspective view of a portion of a finishedor completed concrete wall from which the wall form panels have beenremoved, the view showing one looped end of the tie rod of one of theassemblies preparatory to fracture and removal of said tie rod end andsubsequent removal of the associated plastic frustoconical spacer memberfrom its encompassing socket in the adjacent side surface of the wall;

FIG. 3 is an enlarged fragmentary sectional view taken substantially onthe vertical plane indicated by the line 33 of FIG. 2 and in thedirection of the arrows;

FIG. 4 is a vertical transverse sectional view taken on the line 4-4 ofFIG. 3; and

FIG. 5 is a sectional view similar to FIG. 2 but showing the looped tierod end and its associated spacer member wrested from the socket in theadjacent side surface of the concrete wall.

Referring now to the drawings in detail and in particular to FIG. 1, atypical concrete wall form employing tie rod assemblies embodying andconstructed according to the present invention is designated in itsentirety by the reference numeral 10, while the improved tie rodassemblies which are employed in connection with the wall form are eachdesignated by the reference numeral 12. These tie rod assemblies 12 arecapable of use with a wide variety of concrete wall forms, as, for

example, concrete wall forms employing panels having either wooden ormetal reinforcing studding for the usual rectangular plywood facings orhaving no reinforcing studding whatsoever. Furthermore, the tie rods ofthe assemblies 12 may extend across the concrete wall form 10, either atthe juncture region between adjacent panels or they may bridge the formby extending through centrally dispoed regions of the opposed and spacedapart individual panels. However, for exemplary purposes herein, the tierod assemblies 12 are shown as being associated with a concrete wallform eploying steel-studded prefabricated panels 14 of the type which iscommonly known in the concrete forming industry as Steel-Ply panels.Such panels are manufactured and sold by Symons Corporation of DesPlaines, Ill. and are widely known and used in the concrete constructionindustry. Although only the fragmentary edge regions of abutting pairsof panels are disclosed in FIG. 1 of the drawings herein, it will beunderstood that each panel is of shallow, open, tray-like design andincludes a rectangular plywood facing 16 and a marginal reinforcingframe including vertical frame members 18 and horizontal frame members(not shown). At appropriate levels, intermediate horizontal steelcrossbars 20 extend between and are welded to the opposed vertical framemembers 18. Both the vertical and horizontal frame members are in theform of structural steel bars which are of shallow channel shape incross section, and each bar includes inner and outer outwardly extendingmarginal ribs 22 and 24, and a connecting web portion 26. On the side ofeach web portion that is opposite to the ribs 22 and 24 is a lateralinwardly extending flange 28 on which the adjacent marginal portion ofthe associated plywood facing 16 seats. At vertically spaced regionsalong the outwardly extending ribs 22 and 24 of the vertical framemembers 18 of the panels 14, pairs of transversely-registering notches30 are formed, and these notches, when said vertical frame members 18are in contiguity, define therebetween horizontal channel-like voids 32which are adapted to receive therethrough the adjacent looped ends ofthe tie rods of the tie rod assemblies 12 as will be described in detailpresently. A rectangular slot 34 is formed in the web portion 26 of eachvertical frame member at the level of each pair of notches 30, and suchslot is adapted to receive therethrough the shank portion of ahorizontal T-bolt 36. A vertical wedge 38, which is driven through alongitudinal slot in the shank of the T-bolt 36, serves to place theT-bolt under tension and this draws adjacent or contiguous verticalframe members 18, as well as their associated panels 14, tightlytogether.

The arrangement of parts thus far described is purely conventional andno claim is made herein to any nov elty that may be associated with thesame, the novelty of the present invention residing rather in theparticular novel construction, combination, and arrangement of parts ofthe tie rod assemblies 12. Such assemblies will now be described indetail. Since all of the tie rod assemblies 12 are identicaL-adescription of one of them will suffice for them all.

Still referring to FIG. 1, the illustrated form of tie rod assembly 12involves in its general organization a normally horizontal tie rod 40which is in the form of a length of cylindrical wire or rod stock andhas integral looped ends 42. The latter are adapted to encircle theshanks of the associated T-bolts 36 or otherwise be attached to theopposite panel form sides of the concrete wall form 10. As best shown inFIG. 3 of the drawings, the looped ends 42 of the tie rod 40 are neithercircular nor symmetrical, each such end consisting of a laterally offsetcurved spiral section 44 which merges gradually into a linearly straightsection 46, the distal end of which extends tangentially alongside themain body of the tie rod and is connected thereto by a weld 48 as bestshown in FIG. 3.

At regions spaced inwardly from the looped ends 42, the metal of the tierod is flattened in order to provide weakened portions 49 which arecommonly known in the art as breakbacks and by means of which the loopedends 42 of the tie rod 40 may be readily severed from theconcrete-embedded medial region of the tie rod by twisting them afterhardening of the concrete wall and removal or stripping of the panels 14from the wall.

Mounted on the tie rod 40 and interposed between each breakback 44 andits adjacent looped end 42 is a spacer member 50 of novel design, suchmember constituting the principal feature of the present invention. Aflat washer 52 is interposed between each spacer member 50 and theadjacent breakback 44.

Each spacer member of the tie rod assembly 12 is formed of a relativelyrigid, unyielding plastic material which may be a high density styrene,the member being formed by a suitable molding operation and embodying anopen-ended tubular frusto-conical shell 54, the large and small bases ofwhich present respective circular rims 56 and 58. On the interior of theshell 54 there is provided a series of four quadrilaterally arrangedradial ribs 60 which are tapered in the direction of the small base ofthe frusto-conical shell and terminate thereat. These ribs are formedintegrally with and extend radially inwards from the inner surface ofperiphery of the frusto-conical shell 54 and terminate near the largebase of said shell. The inner edges 62 of the ribs 60 extend inparallelism as clearly shown in FIG. 3, but are relieved on a curvedbias as indicated at 64 in the vicinity of the rim 56 of the large baseof the shell. These relief areas of the ribs directly oppose the weld 48and allow partial nesting of the looped ends 42 within the confines ofthe shell, while at the same time confining the spacer member 50 againstappreciable outward shifting movement away from the breakback 49.

The spacer member 50 at each end of the tie rod 40 is telescopicallyreceived over the tie rod so that the inner edges 62 of the ribs 60 lieclosely alongside the rod and center the latter axially in the member50. The spacer member 50 is captured on the tie rod by means of theassociated washer 52 which bears against the rim 58 of the small base ofthe shell of the spacer member and prevents inward shifting of saidspacer member 50 on the rod, as well as by the weld 48 which contactsthe inner edges 62 of the ribs 60 and prevents the member 50 fromshifting outwardly of the tie rod. A small amount of longitudinal playin a longitudinal or axial direction is preferably but not necessarilyprovided for. The main body of the looped tie rod end 42 projectsoutwardly beyond the large rim 56 of the shell 54 of the spacer member50. As clearly shown in FIGS. 3 and 4 of the drawings, the straightsection 46 of the looped end 42 of the tie rod 40 is eccentricallydisposed with respect to the axis of the tie rod so that it interlocksbetween two adjacent ribs 60 within the confines of the frusto-conicalshell 54 of the spacer member 50 and prevents rotational movement of thetie rod end with respect to the spacer member. This interlockconstitutes a driving connection between the looped tie rod end and thespacer member 50 during the twist-off operation as will be describedpresently.

The herein described tie rod assembly 12 is adapted for use inconnection with a concrete wall form such as the form which isfragmentarily shown in FIG. 1 in substantially the same manner as aconventional or standard tie rod assembly, the looped ends 42 of the tierod 40 being arranged in encircling relation with the shanks of theT-bolts 36 as heretofore set forth and the tie rod being arranged sothat the portions thereof that are im- -mediately inwards of the loopedends 42 project through the channel-like voids 32 between the inner andouter outwardly extending marginal ribs 22 and 24 of adjacent verticalframe members 18. The rims of the large bases of the frusto-conicalshells 54 of the spacer members 50 assume positions of contiguity orabutment with the inner side faces of the inner ribs 22 so that theyserve to seal the adjacent channel-like voids 32 against seepage of wetconcrete out of the space between the sides of the concrete wall form10. The washers 52 which bear inwardly against the breakbacks 44 of thetie rod 40 and abut against the rims 58 of the small bases of the shells54 of the spacer members 50 and hold said spacer members tightly againstthe form sides.

After the concrete has been poured between the two sides of the concreteform and has become set or hardened, the wedges 38 are driven out oftheir connected relation with the slotted shanks of the associatedT-bolts 36 in order to release the panels 14 so that they may bestripped from the resulting concrete wall W (see FIGS. 2 and 5). Themedial region of the tie rod 40, together with the spacer members 50 andtheir associated washers 52, remain embedded within the concrete withthe rims 56 of the large bases of the shells 54 of the spacer membersbeing exposed and flush with the side surfaces of the concrete wall W asshown in FIG. 2 of the drawings. The projecting end portions of the tierod 40 including the looped ends 42 are then worked back and forth tothe extent permitted by any looseness thereof within the spacer members50 and, at the same time, twisted until such time as they break loosefrom the embedded medial portion of the tie rod 40 in the vicinity ofthe breakbacks 49. During this twisting operation, the laterally offsetand eccentrically disposed, linearly straight sections 46 of the tie rod40 establish driving connections between the looped tie rod ends 42 andthe spacer member 50 and cause rotation of the latter, thus breaking thebond between the concrete and the spacer members so that, when thelooped ends are pulled outwardly and away from the side surfaces of theconcrete wall W, the thus loosened spacer members will either fall fromthe wall or they will adhere to the removed tie rod ends 42 due to thepresence of any burrs or offset portions of the metal of the tie rodwhich may be present as a result of the uneven lines of cleavage at thebreak-off points. As

' is the case with conventional frusto-conical spacer members, suchremoval of the spacer members 50 from the completed concrete wall W willresult in the provision of frusto-conical sockets such as is indicatedat 70 in FIG. 5, the spacer members functioning in the manner ofpatterns for the production of such sockets.

In the unlikely event that the looped. ends 42 of the tie rod 40 of thetie rod assembly 12 should pull from the spacer members 50, thus leavingthe latter still present in the frusto-conical sockets 70, the fact thatthe bond between the spacer members and the sockets has been broken byrotation of the spacer members within the sockets will facilitatesubsequent easy fingerremoval of the spacer members.

During removal of the spacer members 50 and the looped tie rod ends 42from the concrete wall W, the associated washers 52 may or may not,depending on chance, remain within the sockets 70. in either event, thesockets may be filled with a suitable patching material (grout) as iscustomary in the art. Inasmuch as during concrete pouring and hardeningoperations, the washers substantially close the inner ends of the spacermembers 50, concrete will not flow outwardly and into the interior ofthe spacer members. These members thus remain in condition forsubsequent reuse with little or no cleaning operations being required.

In manufacturing the tie rod assembly 12 of the present invention at thefactory, a straight or unbent length of wire or rod stock is first cutto the desired or specified length. Thereafter, the washers 52 and thefrustoconical spacing members 50 are mounted on the end portions of thestraight piece of stock and then slid inwards onto the intermediate ormedial portion of the straight piece of stock. After these twooperations, the ends of the piece of wire stock are bent into loop formand subsequently welded in place in order to form the tie rod 40 of theassembly 12. Directly following the bending and welding operations, thespacing members 50 and the washers 52 are slid outwards in order tobring the large bases of the spacing members into interlocked relationwith the welded Y extremities of the looped ends 42 of the tie rod 40.The final step in the manufacture of the tie rod assembly 12 is theformation of the flat breakback portions 49. After formation of suchportions, the outer ends thereof abut against the washers 52 and serveto hold the washers and the frusto-conical spacer members in theirproper position on the tie rod 40.

The invention is not to be limited to the exact arrangement of partsshown in the accompanying drawings or described in this specification asvarious changes in the details of construction may be resorted towithout departing from the spirit or scope of the invention. Therefore,only insofar as the invention is particularly pointed out in theaccompanying claims is the same to be limited.

Having thus described the invention what I claim as new and desire tosecure by letters patent is:

1. As a new article of manufacture, a tie rod assembly adapted for usein connection with a concrete wall form and comprising a tie rod in theform of a length of cylindrical rod stock, said tie rod having a loopportion at one end thereof whereby the tie rod may be attached to oneside of the form, and also having a breakback disposed inwardly fromsaid loop portion, and an integral one-piece spacer membertelescopically disposed on and completely encircling said tie rod andinterposed between said loop portion and the breakback, said spacermember being formed of a rigid molded plastic material and embodying anopen-ended frusto-conical shell having its small rim effectively bearingagainst said breakback, said loop portion of the tie rod being disposedpartially within the confines of the shell and projecting outwardlytherefrom through the large rim of the shell, and an internal rib formedon and disposed within the confines of the shell and effective betweensaid loop portion and shell, whereby upon rotation of the loop portionin either direction, the rib will engage an eccentric portion of theloop and the spacer member will be constrained to rotate bodily with theloop and break the bond existing therebetween and the concrete of thewall that is produced by the form.

2. A tie rod assembly as set forth in claim 1 and wherein a plurality ofcircumferentially spaced radially disposed internal ribs are formed onsaid shell and have the inner edges thereof disposed in the rotationalpath of movement of said loop portion.

3. A tie rod assembly as set forth in claim 2 and wherein four ribs areprovided and the inner edges of one pair of adjacent internal ribsstraddle the cylindrical rod stock of said loop portion in closeproximity thereto whereby, upon rotation of said loop portion in eitherdirection, said spacer member will be constrained to rotate bodilytherewith.

4. A tie rod assembly as set forth in claim 3 and wherein said loopportion embodies a reentrant section which is secured in tangentialfashion to the rod at the base of the loop portion by a weld, the inneredges of the internal ribs lie closely alongside the rod in centeringrelationship and overlap said reentrant section, and the outer edgeregions of the ribs are relieved and afford a clearance for thereentrant section whereby the inner end of the latter and the welddirectly oppose each other so as to confine the spacer member betweenthe breakback and weld against appreciable longitudinal shifting on therod.

UNITED STATES PATENT AND TRADEMARK OFFICE Certificate Patent No.3,785,610 Patented January 15, 1974 Richard T. Dagiel Application havingbeen made by Richard T. Dagiel, the inventor named in the patent aboveidentified, and Symons Corporation, Des Plaines, Illinois, acorporation, of Delaware, the assignee, for the issuance of acertificate under the provisions of Title 35, Section 256, of the UnitedStates Code, adding the name of James C. Shoemaker as a joint inventor,and a showing and proof of facts satisfying the requirements of the saidsection having been submitted, it is this 15th day of July 1975,certified that the name of the said James C. Shoemaker is hereby addedto the said patent as a joint inventor with the said Richard T, Dagiel,

FRED W. SHERLING, Associate Solicitor,

1. As a new article of manufacture, a tie rod assembly adapted for usein connection with a concrete wall form and comprising a tie rod in theform of a length of cylindrical rod stock, said tie rod having a loopportion at one end thereof whereby the tie rod may be attached to oneside of the form, and also having a breakback disposed inwardly fromsaid loop portion, and an integral one-piece spacer membertelescopically disposed on and completely encircling said tie rod andinterposed between said loop portion and the break-back, said spacermember being formed of a rigid molded plastic material and embodying anopen-ended frusto-conical shell having its small rim effectively bearingagainst said breakback, said loop portion of the tie rod being disposedpartially within the confines of the shell and projecting outwardlytherefrom through the large rim of the shell, and an internal rib formedon and disposed within the confines of the shell and effective betweensaid loop portion and shell, whereby upon rotation of the loop portionin either direction, the rib will engage an eccentric portion of theloop and the spacer member will be constrained to rotate bodily with theloop and break the bond existing therebetween and the concrete of thewall that is produced by the form.
 2. A tie rod assembly as set forth inclaim 1 and wherein a plurality of circumferentially spaced radiallydisposed internal ribs are formed on said shell and have the inner edgesthereof disposed in the rotational path of movement of said loopportion.
 3. A tie rod assembly as set forth in claim 2 and wherein fourribs are provided and the inner edges of one pair of adjacent internalribs straddle the cylindrical rod stock of said loop portion in closeproximity thereto whereby, upon rotation of said loop portion in eitherdirection, said spacer member will be constrained to rotate bodilytherewith.
 4. A tie rod assembly as set forth in claim 3 and whereinsaid loop portion embodies a reentrant section which is secured intangential fashion to the rod at the base of the loop portion by a weld,the inner edges of the internal ribs lie closely alongside the rod incentering relationship and overlap said reentrant section, and the outeredge regions of the ribs are relieved and afford a clearance for thereentrant section whereby the inner end of the latter and the welddirectly oppose each other so as to confine the spacer member betweenthe breakback and weld against appreciable longitudinal shifting on therod.